package api;

import cn.hutool.core.util.StrUtil;
import cn.hutool.json.JSONUtil;
import lombok.SneakyThrows;
import util.AppVar;
import util.DBUtils;
import util.ResultUtils;

import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
import java.sql.Connection;
import java.sql.PreparedStatement;

/**
 * 阅读量 +1
 */
@WebServlet("/addrcount")
public class AddReadCountServlet extends HttpServlet {
    @SneakyThrows
    @Override
    protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        String msg = "未知错误！";
        int data = 0;
        // 1.得到前端参数并进行效验
        String aidStr = req.getParameter("aid");
        if (!StrUtil.isBlank(aidStr)) {
            // 2.将访问量 +1，得到执行的结果
            int aid = Integer.valueOf(aidStr);
            if (aid > 0) {
                Connection connection = DBUtils.getConnection();
                String sql = "update article set readcount=readcount+1 where aid=?";
                PreparedStatement statement = connection.prepareStatement(sql);
                statement.setInt(1, aid);
                data = statement.executeUpdate();
                // 关闭资源
                DBUtils.close(null, statement, connection);
                msg = "";
            } else {
                msg = "参数错误！";
            }
        } else {
            msg = "参数错误！";
        }
        // 3.将结果返回给前端
        resp.setContentType(AppVar.RESPONSE_CONTENTTYPE_JSON);
        resp.getWriter().println(
                JSONUtil.toJsonStr(ResultUtils.toResult(200, data, msg))
        );
    }
}